Numerous machines are actuated by coins, or tokens, or the like and they contain a coin receptacle for storing said coins, ect. Examples of such "slot machines" include pay phones, vending machines, and meters for paying for car parking
In such machines, coins are inserted via one or more slots and they pass through a coin selector of varying degrees of complexity which verifies that the coins are not counterfeit and which also establishes the value of the coins. Reject coins are returned to the user while accepted coins are sent via a chute to a coin receptacle. In some cases, the chute may include a coin hold device which temporarily retains accepted coins until the user actuates a coin-encashing control which allows the coins to go to the coin receptacle. Until the user actuates the coin-encashing control, the user retains the possibility of abandoning the operation and recovering the coins.
The organization in charge of the machines must periodically collect the coins contained in the receptacle. In some cases the receptacle is fixed in the machine and collection takes place by opening a trap door communicating with the receptacle. In other cases the receptacle is in the form of a removable safe. Collection then consists in removing full receptacles and replacing them with empty receptacles. European patent number 44 754 in the name of FLONIC describes a parking fee terminal equipped with the first type of coin receptacle.
One of the problems with managing such machines is defining when to collect coins from them. If collections are performed too frequently relative to the real capacity of each receptacle, then operating expenses are too high. In contrast, if collections are not performed frequently enough, then the receptacles are in danger of overflowing. Overflowing is always bad, since it either causes coins to be lost or else it disturbs the overall operation of the coin circuit in the machine. If the receptacle is removable, coin overflow may jam the receptacle and prevent it from being removed. If the receptacle if fixed, coin overflow can fill up the coin arrival chute and hinder operation of systems disposed upstream from the chute. It is therefore always desirable to provide a device in such a machine for detecting that its coin receptacle is full.
One possible detection system consists in taking advantage of the fact that an electronic coin selector can also be used to count all the coins it has selected. However this solution is not satisfactory since coins come in different sizes and the way in which they pile up in the receptacle is random. In order to perform detection by counting coins, it is therefore necessary to provide a considerable safety margin over optimum filling.
In order to remedy these drawbacks, an object of the invention is to provide a device for detecting that a coin receptacle is full by detecting the level to which a receptacle is actually filled regardless of the nature of the coins it contains.